Water pollution involves the release into lakes, streams, rivers, and oceans of substances that become dissolved or suspended in the water or deposited upon the bottom and accumulate to the extent that they interfere with the functioning of aquatic ecosystems. It may also include the release of energy in the form of radioactivity or heat, as in the case of thermal pollution. Any body of water has the capacity to absorb, break down, or recycle introduced materials. Under normal circumstances, inorganic substances are widely dispersed and have little or no effect on life within the bodies of water into which they are released; organic materials are broken down by bacteria or other organisms and converted into a form in which they are useful to aquatic life. But, if the capacity of a body of water to dissolve, disperse, or recycle is exceeded, all additional substances or forms of energy become pollutants.
Pollution may begin as water moves through the air, if the air is polluted. Soil erosion adds silt as a pollutant. The use of chemical fertilizers, pesticides, or other materials on watershed lands is an additional factor contributing to water pollution. The runoff from septic tanks and the outflow of manures from livestock feedlots along the watershed are sources of organic pollutants. Industries located along waterways downstream contribute a number of chemical pollutants, some of which are toxic if present in any concentration. Finally, cities and towns contribute their loads of sewage and other urban wastes.
This handy list of information sources points to websites that tell you what the problems are, how they're caused, and how we can attempt to solve them. It's not an exhaustive list of information, but it is comprehensive. It'll give you an overview of most of the issues involved in water pollution.
Governments and organizations dealing with general water quality issues.
an excellent and detailed introduction for kids to the whole subject by David Krantz and Brad Kifferstein
EU Environmental Legislation - Water
European Parliament Fact Sheets Last update: 3 June 1999 4.9.3. Water pollution LEGAL BASIS AND OBJECTIVES * 4.9.1. ACHIEVEMENTS
Water pollution Enichem under fire in Venice Pollution levels in the Venice Lagoon are among the worst in the world, according to Greenpeace.